JBL 4344 Clones

[christo]

Each piece is individually attached to the baffle with screws. To ensure the lens line up uniformly I had a template made to allow for the predrilling of the plate screw holes. The template is centered on the baffle by using the existing bolt holes for the horn. That was my original plan but it didn’t end up that way (wrong size holes for centering), for me it did not matter as I had not drilled the bolt holes in the baffle yet so I was able to just use the pilot holes.



Here is the layout of the template



Once the lens mounting screw holes have been predrilled it is just a matter of attaching the plates one at a time from the bottom up.

[christo]

For the SS LPAD foilcal I used a vinyl sticker, I had sections of it made clear so the SS is still visible beneath it.

[christo]

But what I really want to see is some pictures of how you assembled that beautiful stainless steel lense. Did you weld the pieces together, tap and thread them, or use regular old nuts and bolts? You might want to consider making a few pair for some of us 4343/4344 owners , I know that I'd certainly be interested. Great work! regards, Paul from Providence

Thanks Paul

If any members are interested in the Stainless Steel 2308 lens please PM me, if there is sufficient interest I'll see what can be done – not promising anything at this point.

Chris

[christo]

Can you show how you trimmed the walnut trim in angle on the front?,

The trim is chamfered at 30 degrees. Scrap wood is clamped at each end to allow the router bit guide wheel to roll straight off the edge of the box. Once each side has been chamfered you can’t do this for the top or bottom you have to use a straight edged to guide the router. Cause if you don’t the router guide wheel would follow the chamfered edge and a grown man will cry. The following pictures are from my B380 project but the technique is the same.

[christo]

You just started making the X-overs....??, how did you know what to buy (quality)?,

Well let’s just say “I just started assembling X-overs” I’ll leave the making to the experts.

I did my research; Google Advanced Search is your friend when looking for information in this web site. Search using “Giskard's equivalent network”.

There is tons of information on X-overs within this web with the associated part list.

I used the 2405H and 2425J circuits from “Giskard's equivalent network” and the JBL 4344 MKII for the 2123. I have redrawn the schematic from the scanned imaged in the web site. To any experts out there if I have miss-drawn the four 36.0 µF Caps that represent the two 72 µF Caps on the original JBL schematic let me know and I’ll fix. I’m no expert in this area.


This is the parts list I used and were sourced from www.solen.ca.

[Amnes]

Inspiring thread - thank you for posting.

[Chas]

Congratulations on a fine project.

Beautiful work and excellent documentation!

I know what you mean about inserting those TD-2002s... Bo and I heard the same thing when we popped a pair into his 4345s. It was a surprising difference!


Widget

Even better with cc or upgraded caps, too.

[christo]

Well let’s just say “I just started assembling X-overs” I’ll leave the making to the experts.

I did my research; Google Advanced Search is your friend when looking for information in this web site. Search using “Giskard's equivalent network”.

There is tons of information on X-overs within this web with the associated part list.

I used the 2405H and 2425J circuits from “Giskard's equivalent network” and the JBL 4344 MKII for the 2123. I have redrawn the schematic from the scanned imaged in the web site. To any experts out there if I have miss-drawn the four 36.0 µF Caps that represent the two 72 µF Caps on the original JBL schematic let me know and I’ll fix. I’m no expert in this area.


This is the parts list I used and were sourced from www.solen.ca.

The network diagram has a typo with the capacitors in the 2405 circuit. The original schematic had a pair of 3.3 uF this is incorrect. The pairing should be 3.3 uF and 3.9 uF. The parts list in the original post is correct.

Below is the corrected schematic.

[Dr.db]

I used Silicone to glue the ports (ABS or sewage pipe) in to the cabinet

Once I was told to never use silicone in a speaker enclosure due to it´s agressive degassing.
It could dissolve the glue of driver-cones and suspensions!

I have never tried, so I cannot confirm this quote but I just wanted to let you know...

[Woody Banks]

Beautiful work and documentation. Thanks for sharing.

[fencki]

hi.
can i use the 2420 instead of the 2426 (TAD) for the HF?
or do i have to adapt the R´s, C´s and L´s?

thx

[christo]

hi.
can i use the 2420 instead of the 2426 (TAD) for the HF?
or do i have to adapt the R´s, C´s and L´s?

thx

The 2420 = LE85 which will work fine with the crossover, I have tried this.

[christo]

Beautiful work and documentation. Thanks for sharing.

Thanks Woody I have always admired your work !

[christo]

Once I was told to never use silicone in a speaker enclosure due to it´s agressive degassing.
It could dissolve the glue of driver-cones and suspensions!

I have never tried, so I cannot confirm this quote but I just wanted to let you know...

I have never heard that, the boxes sat around for a week before I put the 2235s back in so hopefully the initial degassing would have occurred. It been two year's now with no issues.

PS Like your work on your tribute project!

[fencki]

The 2420 = LE85 which will work fine with the crossover, I have tried this.

thx for your answer.
you helped a lot!

i have one more question for my JBL 4345 clones.
beacause i have no 2122h i got one 2123h.
can i use this crossover from 4344 MK2 with chassis 2123h and build up the 3145 crossover?:

http://www.audioheritage.org/vbullet...l=1#post397270
(#53)


please help with that too...
so i can start to order the parts for the crossover.

big thx!!!



btw you did a REALLY GREAT job with ur JBL´s. just phantastic!